1 # Pleroma: A lightweight social networking server
2 # Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
3 # SPDX-License-Identifier: AGPL-3.0-only
5 defmodule Pleroma.User.Search do
10 @similarity_threshold 0.25
13 def search(query_string, opts \\ []) do
14 resolve = Keyword.get(opts, :resolve, false)
15 following = Keyword.get(opts, :following, false)
16 result_limit = Keyword.get(opts, :limit, @limit)
17 offset = Keyword.get(opts, :offset, 0)
19 for_user = Keyword.get(opts, :for_user)
21 # Strip the beginning @ off if there is a query
22 query_string = String.trim_leading(query_string, "@")
24 maybe_resolve(resolve, for_user, query_string)
27 Repo.transaction(fn ->
28 Ecto.Adapters.SQL.query(
30 "select set_limit(#{@similarity_threshold})",
35 |> search_query(for_user, following)
36 |> paginate(result_limit, offset)
43 defp search_query(query_string, for_user, following) do
45 |> base_query(following)
46 |> search_subqueries(query_string)
49 |> boost_search_rank_query(for_user)
51 |> order_by(desc: :search_rank)
52 |> maybe_restrict_local(for_user)
55 defp base_query(_user, false), do: User
56 defp base_query(user, true), do: User.get_followers_query(user)
58 defp paginate(query, limit, offset) do
59 from(q in query, limit: ^limit, offset: ^offset)
62 defp union_subqueries({fts_subquery, trigram_subquery}) do
63 from(s in trigram_subquery, union_all: ^fts_subquery)
66 defp search_subqueries(base_query, query_string) do
68 fts_search_subquery(base_query, query_string),
69 trigram_search_subquery(base_query, query_string)
73 defp distinct_query(q) do
74 from(s in subquery(q), order_by: s.search_type, distinct: s.id)
77 defp maybe_resolve(true, user, query) do
78 case {limit(), user} do
80 {:unauthenticated, %User{}} -> User.get_or_fetch(query)
81 {:unauthenticated, _} -> :noop
82 {false, _} -> User.get_or_fetch(query)
86 defp maybe_resolve(_, _, _), do: :noop
88 defp maybe_restrict_local(q, user) do
89 case {limit(), user} do
90 {:all, _} -> restrict_local(q)
91 {:unauthenticated, %User{}} -> q
92 {:unauthenticated, _} -> restrict_local(q)
97 defp limit, do: Pleroma.Config.get([:instance, :limit_to_local_content], :unauthenticated)
99 defp restrict_local(q), do: where(q, [u], u.local == true)
101 defp boost_search_rank_query(query, nil), do: query
103 defp boost_search_rank_query(query, for_user) do
104 friends_ids = User.get_friends_ids(for_user)
105 followers_ids = User.get_followers_ids(for_user)
107 from(u in subquery(query),
112 CASE WHEN (?) THEN 0.5 + (?) * 1.3
113 WHEN (?) THEN 0.5 + (?) * 1.2
114 WHEN (?) THEN (?) * 1.1
117 u.id in ^friends_ids and u.id in ^followers_ids,
119 u.id in ^friends_ids,
121 u.id in ^followers_ids,
129 @spec fts_search_subquery(User.t() | Ecto.Query.t(), String.t()) :: Ecto.Query.t()
130 defp fts_search_subquery(query, term) do
133 |> String.replace(~r/\W+/, " ")
136 |> Enum.map(&(&1 <> ":*"))
147 setweight(to_tsvector('simple', regexp_replace(?, '\\W', ' ', 'g')), 'A') ||
148 setweight(to_tsvector('simple', regexp_replace(coalesce(?, ''), '\\W', ' ', 'g')), 'B'),
149 to_tsquery('simple', ?),
161 (setweight(to_tsvector('simple', regexp_replace(?, '\\W', ' ', 'g')), 'A') ||
162 setweight(to_tsvector('simple', regexp_replace(coalesce(?, ''), '\\W', ' ', 'g')), 'B')) @@ to_tsquery('simple', ?)
169 |> User.restrict_deactivated()
172 @spec trigram_search_subquery(User.t() | Ecto.Query.t(), String.t()) :: Ecto.Query.t()
173 defp trigram_search_subquery(query, term) do
177 # ^1 gives 'Postgrex expected a binary, got 1' for some weird reason
178 search_type: fragment("?", 1),
181 "similarity(?, trim(? || ' ' || coalesce(?, '')))",
187 where: fragment("trim(? || ' ' || coalesce(?, '')) % ?", u.nickname, u.name, ^term)
189 |> User.restrict_deactivated()